The conventional LED lamps now on the market can generate light with a small amount of electric power, but also generate heat at the same time. To make replacement of the LED lamp easier a protective case is usually provided in the center thereof for user holding. The protective case traps the generated heat inside and results in undesirable heat dissipation. Hence the LED lamp is prone to damaging and results in a lower durability. To remedy the aforesaid problem some producers develop a technique by attaching the LED lamp to a lower side of a heat transfer plate and providing spaced radiation fins above the heat transfer plate. However, the power supply holder above the LED lamp does not have cooling means, a great amount of heat is generated during use. Although the heat transfer plate can receive the heat generated by the LED lamp and transfer to the radiation fins for dispersion, the heated radiation fins reciprocate the heat one another to make contact heat transfer function saturated and result in a higher temperature on the whole lighting feature. Cooling becomes even more difficult, especially on the power supply holder. Hence the life span of the LED lamp suffers. How to improve heat dissipation of the LED lamp is an issue remained to be overcome in the industry.